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Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite (open access)

Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
System: The UNT Digital Library
SEARCH FOR MAGNETIC MONOPOLES IN THE LUNAR SAMPLES OF APOLLO11. (open access)

SEARCH FOR MAGNETIC MONOPOLES IN THE LUNAR SAMPLES OF APOLLO11.

An electromagnetic search for magnetic monopoles of the minimum size predicted by Dirac, or of any larger magnitude, has been performed on 8.37 kilograms of lunar surface material returned by the Apollo 11 crew. No monopole was found. This experiment sets new limits on the production cross section for monopoles, and on their occurrence in cosmic radiation.
Date: December 1, 1969
Creator: Alvarez, Luis W.; Eberhard, Philippe H.; Ross, Ronald R. & Watt,Robert D.
System: The UNT Digital Library
PERTURBATION-THEORY RULES FOR COMPUTING THE SELF-ENERGY OPERATOR IN QUANTUM STATISTICAL MECHANICS (open access)

PERTURBATION-THEORY RULES FOR COMPUTING THE SELF-ENERGY OPERATOR IN QUANTUM STATISTICAL MECHANICS

Highly convenient rules are given for the general term in the time-independent perturbation-theory expansion for the self-energy operator of quantum statistical mechanics. The rules are derived by starting from the usual formalism involving time-dependent Green's functions. The well-known formulas for thermodynamic quantities in terms of the self-energy operator are included for completeness.
Date: December 17, 1962
Creator: Baym, Gordon & Sessler, Andrew M.
System: The UNT Digital Library
Experiments on Forming Intense Rings of Electrons Suitable for the Acceleration of Ions (open access)

Experiments on Forming Intense Rings of Electrons Suitable for the Acceleration of Ions

Electrons were injected from a 3.3-MeV 300-A accelerator into a circular orbit in a pulsed magnetic field. Trapped ring currents of 150 A (4 x 10{sup 12} electrons) were magnetically compressed from 19 cm to 3.5 cm radii and simultaneously accelerated from 3.3 MeV to 18 MeV in energy. The rms dimensions of the cross section of the ring after compression were a = 2.3 {+-} 0.2 mm radially and b = 1.6 {+-} 0.2 mm axially. The lifetime of the ring was typically 5.5 msec, and was determined by the decay of the magnetic field after compression. This lifetime could be decreased by the addition of hydrogen gas, indicating the focusing effect of the trapped positive ions.
Date: December 16, 1968
Creator: Keefe, D.; Lambertson, G. R.; Laslett, L. J.; Perkins, W. A.; Peterson, J. M.; Sessler, A. M. et al.
System: The UNT Digital Library
ABIOGENIC INFORMATION COUPLING BETWEEN NUCLEIC ACID AND PROTEIN,OR, HOW PROTEIN AND DNA WERE MARRIED (open access)

ABIOGENIC INFORMATION COUPLING BETWEEN NUCLEIC ACID AND PROTEIN,OR, HOW PROTEIN AND DNA WERE MARRIED

There is now experimental evidence for selectivity between the amino acid and the nucleic acid base which is the beginning of the chemical translation process from one linear system to the other. The linear system of the nucleic acid is, of course, an excellent place to store the information, whereas the linear system of the polypeptide, on the other hand, is the versatile system which can perform many different types of reactions but is unable to store information reliably. The experiments the author has described here may represent the beginning of the method of coupling of those two essential qualities which are required for the generation and evolution of a living organism.
Date: December 1, 1968
Creator: Calvin, Melvin
System: The UNT Digital Library
CORRELATIONS BETWEEN PHOTOINDUCED EPR AND PHOTOCONDUCTIVITY INTONE-THF SOLUTION CHARGE-TRANSFER COMPLEX (open access)

CORRELATIONS BETWEEN PHOTOINDUCED EPR AND PHOTOCONDUCTIVITY INTONE-THF SOLUTION CHARGE-TRANSFER COMPLEX

Reversible photoinduced electron paramagnetic resonance (EPR) signals and photoconductivity were observed when a solution of tetracyancethylene (TCNE) in tetrahydrofuran (THF) was irradiated in the charge-transfer band of the complex formed between these two compounds. The eleven-line hyperfine structure of the EPR spectrum which was obtained demonstrated the presence of TCNE negative ion radical. The concentration of this radical was found to be directly proportional to the square root of the light intensity. Second order decay kinetics were followed when the light was shut off. Both the EPR signal and the photoconductivity rose initially as the square of the time. The latter portions of the growth curves could be fit to the latter portions of a hyperbolic tangential growth curve. From these data a reaction mechanism was proposed. The rate law dn/dt + kn{sup 2} = {alpha}L(1-e{sup -{beta}t}) = 0, where n = the concentration of radicals, t = the time, k, {alpha}, and {beta} are rate constants, and L = the light intensity, described both the photo-induced EPR and the photoconductivity within the limits of experimental accuracy.
Date: December 8, 1964
Creator: Ilten, David F. & Calvin, Melvin
System: The UNT Digital Library
HIGH-ENERGY-PHYSICS EXPERIMENTS WITH POLARIZED TARGETS (open access)

HIGH-ENERGY-PHYSICS EXPERIMENTS WITH POLARIZED TARGETS

If we are to do a workmanlike job of studying the strong interactions it is imperative that we have knowledge of the spin dependence of the forces. This implies that polarization experiments are essential. Already Bareyre, Bricman, Stirling and Villet have shown that pion-proton polarization experiments should be interpreted as indicating two new resonances not previously seen by other methods. The present-day approach to determining detailed pion-proton scattering amplitudes is to use measured differential cross sections, polarization measurements, dispersion relations, and isospin conservation rules. Further assumptions are unitarity of the S matrix and the short-range nature of strong interactions. In the more distant future I hope we may see the day when the scattering experiments will be sufficiently detailed that the dispersion relations will not be necessary to the interpretation of results. Then the dispersion relations may themselves be checked experimentally, rather than being assumed. I see, then, an early period of polarization experiments followed by a later period in which more extensive experimental results will be called for. For the pion-proton system the first period seems well progressed, based on measurements of differential cross section and P, the polarization. In the second period more complex experiments should be required, …
Date: December 1, 1966
Creator: Chamberlain, Owen
System: The UNT Digital Library
THE LIFETIME OF BACTERIAL MESSENGER RNA (open access)

THE LIFETIME OF BACTERIAL MESSENGER RNA

Puromycin, an inhibitor of protein synthesis, appears to act as an inhibitor at additional sites during the induction of {beta}-galactosidase synthesis. No inhibition of the reactions proceeding during the first 20 seconds of induction was observed, but puromycin seems to prevent the accumulation of messenger RNA during the period between 20 seconds and the first appearance of enzyme activity after 3 minutes. When cells from a stationary culture are placed in fresh medium containing inducer for {beta}-galactosidase, growth, as represented by increase in turbidity and by total protein synthesis, starts within 30 seconds. By contrast, {beta}-galactosidase synthesis is greatly delayed compared with induction during exponential growth. Two other inducible enzymes show similar lags, but malic dehydrogenase, which requires no external inducer, shows no lag. The lags are not due to catabolite repression phenomena. They cannot be reduced by pretreatment of the culture with inducer, or by supplementing the fresh medium with amino acids or nucleotides. The lag is also demonstrated by an i{sup -} mutant constitutive for {beta}-galactosidase synthesis. An inhibitor of RNA synthesis, 6-azauracil, preferentially inhibits {beta}-galactosidase synthesis compared with growth in both inducible and constitutive strains. It is suggested that these observations, together with many reports in the …
Date: December 1, 1963
Creator: Moses, V. & Calvin, M.
System: The UNT Digital Library
[Article: Conference for County Medical Society Officials] (open access)

[Article: Conference for County Medical Society Officials]

Article from the December 1960 issue of the Texas State Journal of Medicine listing the program for the Conference for County Medical Society Officials, to be held in Austin on Saturday, January 28, 1961.
Date: December 1960
Creator: unknown
System: The Portal to Texas History
THERMAL STUDY OF CRYSTAL FIELD SPLITTINGS IN ERBIUM ETHYLSULFATE (open access)

THERMAL STUDY OF CRYSTAL FIELD SPLITTINGS IN ERBIUM ETHYLSULFATE

The heat capacities of erbium and yttrium ethylsulfates were measured in the range 12-300 deg K. The magnetic contribution of the erbium ion was evaluated with the help of an assumption concernlng the difference in lattice contributions between the erbium and yttrium salts. The contribution agrees, to within experimental error, with the experimental energy level scheme for the /sup 4/I/ sub 15/2/ state previously published. (auth)
Date: December 1, 1962
Creator: Gerstein, B. C.; Penney, C. J. & Spedding, F. H.
System: The UNT Digital Library
PERTURBATION THEORY OF MANY-BOSON SYSTEMS (open access)

PERTURBATION THEORY OF MANY-BOSON SYSTEMS

A noncanonical transformation of the boson creation and annihilation operators is performed in order to obtain a Hamiltonian which can be treated by the standard methods of field-theoretic perturbation theory. The standard results of Belyaev (with a slight modification) are rederived by this technique. (auth)
Date: December 15, 1962
Creator: Kromminga, A.J. & Bolsterli, M.
System: The UNT Digital Library
Radiotracking of Ducks, Deer and Toads. Technical Report No. 6 (open access)

Radiotracking of Ducks, Deer and Toads. Technical Report No. 6

None
Date: December 1, 1963
Creator: Tester, J. R.
System: The UNT Digital Library
Grounding of Beta Sources by an Auxiliary Alpha Source (open access)

Grounding of Beta Sources by an Auxiliary Alpha Source

A Po/sup 210/ source was used to furnish a reliab1e ground for both electron and positron sources. This was done to prevent the electron and positron sources from charging during BETA spectral studies in magnetic lens spectrometers. An approximately 20- mu c Po/sup 210/ source was placed 1.2 in. behind a 4- mu c Na/sup 2 / 2>s positron emitter backed by 20- mu g/cm/sup 2/ Formvar in the spectrometer; this arrangement resulted in a charging rate decrease of approximately 80%. When the source was placed 0.5 in. away, no charging was detectable over a period of more than one week. The discharge is attributed mainly to the loss of electrons from the source and backing caused by ionization of alpha particles since few alpha particles are stopped near the source. (B.O.G.)
Date: December 1, 1960
Creator: Nichols, R. T. & Jensen, E. N.
System: The UNT Digital Library
Np-237 and Pu-238 Separation at the Savannah River Plant (open access)

Np-237 and Pu-238 Separation at the Savannah River Plant

None
Date: December 1, 1963
Creator: Poe, W. L.; Joyce, A. W. & Martens, R. I.
System: The UNT Digital Library
U.S. Department of Energy physical protection upgrades at the Latvian Academy of Sciences Nuclear Research Center, Latvia (open access)

U.S. Department of Energy physical protection upgrades at the Latvian Academy of Sciences Nuclear Research Center, Latvia

Approximately five years ago, the Safe, Secure Dismantlement program was started between the United States and countries of the Former Soviet Union (FSU). The purpose of the program is to accelerate progress toward reducing the risk of nuclear weapons proliferation, including such threats as theft, diversion, and unauthorized possession of nuclear materials. This would be accomplished by strengthening the material protection, control, and accounting systems within the FSU countries. This paper describes: the process involved, from initial contacting to project completion, for the physical protection upgrades now in place at the LNRC; the intervening activities; and a brief overview of the technical aspects of the upgrades.
Date: December 31, 1966
Creator: Haase, M.; Hine, C.; Robertson, C.; Soo Hoo, M. S.; Engling, E.; Lapenas, A. et al.
System: The UNT Digital Library
Intermediate Phases in Binary Systems of Technetium-99 With Several Transition Elements (open access)

Intermediate Phases in Binary Systems of Technetium-99 With Several Transition Elements

An exploratory survey was made of the intermediate phases formed when Tc/ sup 99/ is alloyed with the Sc, Ti, V, Cr, Mn, and Fe-group elements. A total of nineteen intermediate phases were identified and found to be isomorphous with the Cr/sub 3/O-type, CsCl-type, MgZn/sub 2/-type, gamma -phase, or sigma -phase structure. The alloying characteristics of Tc are rationalized in terms of periodic table relationships. (auth)
Date: December 1, 1962
Creator: Darby, J. B., Jr.; Lam, D. J.; Norton, L. J. & Downey, J. W.
System: The UNT Digital Library